Electrocardiography patch

ABSTRACT

An electrocardiography patch is provided. A backing forms an elongated strip with a mid-section connecting two ends of the backing. The mid-section is narrower than the two ends of the backing. An electrocardiographic electrode is provided on each end of the backing to capture electrocardiographic signals. A flexible circuit includes a pair of circuit traces electrically coupled to the electrocardiographic electrodes. A wireless transceiver communicates at least a portion of the electrocardiographic signals.

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional patent application is a continuation of U.S. patentapplication Ser. No. 16/241,929, filed Jan. 7, 2019, pending, which is acontinuation of U.S. Pat. No. 10,172,534, issued Jan. 8, 2019, which isa continuation of U.S. Pat. No. 9,820,665, issued Nov. 21, 2017, whichis a continuation of U.S. Pat. No. 9,433,367, issued Sep. 6, 2016, whichis a continuation-in-part of U.S. Pat. No. 9,545,204, issued Jan. 17,2017 and a continuation-in-part of U.S. Pat. No. 9,730,593, issued Aug.15, 2017, and further claims priority under 35 U.S.C. § 119(e) to U.S.Provisional Patent application, Ser. No. 61/882,403, filed Sep. 25,2013, the disclosures of which are incorporated by reference.

FIELD

This application relates in general to electrocardiographic monitoringand, in particular, to an electrocardiography patch.

BACKGROUND

The heart emits electrical signals as a by-product of the propagation ofthe action potentials that trigger depolarization of heart fibers. Anelectrocardiogram (ECG) measures and records such electrical potentialsto visually depict the electrical activity of the heart over time.Conventionally, a standardized set format 12-lead configuration is usedby an ECG machine to record cardiac electrical signals fromwell-established traditional chest locations. Electrodes at the end ofeach lead are placed on the skin over the anterior thoracic region ofthe patient's body to the lower right and to the lower left of thesternum, on the left anterior chest, and on the limbs. Sensed cardiacelectrical activity is represented by PQRSTU waveforms that can beinterpreted post-ECG recordation to derive heart rate and physiology.The P-wave represents atrial electrical activity. The QRSTU componentsrepresent ventricular electrical activity.

An ECG is a tool used by physicians to diagnose heart problems and otherpotential health concerns. An ECG is a snapshot of heart function,typically recorded over 12 seconds, that can help diagnose rate andregularity of heartbeats, effect of drugs or cardiac devices, includingpacemakers and implantable cardioverter-defibrillators (ICDs), andwhether a patient has heart disease. ECGs are used in-clinic duringappointments, and, as a result, are limited to recording only thoseheart-related aspects present at the time of recording. Sporadicconditions that may not show up during a spot ECG recording requireother means to diagnose them. These disorders include fainting orsyncope; rhythm disorders, such as tachyarrhythmias andbradyarrhythmias; apneic episodes; and other cardiac and relateddisorders. Thus, an ECG only provides a partial picture and can beinsufficient for complete patient diagnosis of many cardiac disorders.

Diagnostic efficacy can be improved, when appropriate, through the useof long-term extended ECG monitoring. Recording sufficient ECG andrelated physiology over an extended period is challenging, and oftenessential to enabling a physician to identify events of potentialconcern. A 30-day observation period is considered the “gold standard”of ECG monitoring, yet achieving a 30-day observation day period hasproven unworkable because such ECG monitoring systems are arduous toemploy, cumbersome to the patient, and excessively costly. Ambulatorymonitoring in-clinic is implausible and impracticable. Nevertheless, ifa patient's ECG could be recorded in an ambulatory setting, therebyallowing the patient to engage in activities of daily living, thechances of acquiring meaningful information and capturing an abnormalevent while the patient is engaged in normal activities becomes morelikely to be achieved.

For instance, the long-term wear of ECG electrodes is complicated byskin irritation and the inability ECG electrodes to maintain continualskin contact after a day or two. Moreover, time, dirt, moisture, andother environmental contaminants, as well as perspiration, skin oil, anddead skin cells from the patient's body, can get between an ECGelectrode, the non-conductive adhesive used to adhere the ECG electrode,and the skin's surface. All of these factors adversely affect electrodeadhesion and the quality of cardiac signal recordings. Furthermore, thephysical movements of the patient and their clothing impart variouscompressional, tensile, and torsional forces on the contact point of anECG electrode, especially over long recording times, and an inflexiblyfastened ECG electrode will be prone to becoming dislodged. Moreover,dislodgment may occur unbeknownst to the patient, making the ECGrecordings worthless. Further, some patients may have skin that issusceptible to itching or irritation, and the wearing of ECG electrodescan aggravate such skin conditions. Thus, a patient may want or need toperiodically remove or replace ECG electrodes during a long-term ECGmonitoring period, whether to replace a dislodged electrode, reestablishbetter adhesion, alleviate itching or irritation, allow for cleansing ofthe skin, allow for showering and exercise, or for other purpose. Suchreplacement or slight alteration in electrode location actuallyfacilitates the goal of recording the ECG signal for long periods oftime.

Conventionally, Holter monitors are widely used for long-term extendedECG monitoring. Typically, they are used for only 24-48 hours. A typicalHolter monitor is a wearable and portable version of an ECG that includecables for each electrode placed on the skin and a separatebattery-powered ECG recorder. The cable and electrode combination (orleads) are placed in the anterior thoracic region in a manner similar towhat is done with an in-clinic standard ECG machine. The duration of aHolter monitoring recording depends on the sensing and storagecapabilities of the monitor, as well as battery life. A “looping” Holtermonitor (or event) can operate for a longer period of time byoverwriting older ECG tracings, thence “recycling” storage in favor ofextended operation, yet at the risk of losing event data. Althoughcapable of extended ECG monitoring, Holter monitors are cumbersome,expensive and typically only available by medical prescription, whichlimits their usability. Further, the skill required to properly placethe electrodes on the patient's chest hinders or precludes a patientfrom replacing or removing the precordial leads and usually involvesmoving the patient from the physician office to a specialized centerwithin the hospital or clinic.

The ZIO XT Patch and ZIO Event Card devices, manufactured by iRhythmTech., Inc., San Francisco, Calif., are wearable stick-on monitoringdevices that are typically worn on the upper left pectoral region torespectively provide continuous and looping ECG recording. The locationis used to simulate surgically implanted monitors. Both of these devicesare prescription-only and for single patient use. The ZIO XT Patchdevice is limited to a 14-day monitoring period, while the electrodesonly of the ZIO Event Card device can be worn for up to 30 days. The ZIOXT Patch device combines both electronic recordation components,including battery, and physical electrodes into a unitary assembly thatadheres to the patient's skin. The ZIO XT Patch device uses adhesivesufficiently strong to support the weight of both the monitor and theelectrodes over an extended period of time and to resist disadherancefrom the patient's body, albeit at the cost of disallowing removal orrelocation during the monitoring period. Moreover, throughoutmonitoring, the battery is continually depleted and battery capacity canpotentially limit overall monitoring duration. The ZIO Event Card deviceis a form of downsized Holter monitor with a recorder component thatmust be removed temporarily during baths or other activities that coulddamage the non-waterproof electronics. Both devices representcompromises between length of wear and quality of ECG monitoring,especially with respect to ease of long term use, female-friendly fit,and quality of atrial (P-wave) signals.

In addition, with the advent of wireless communications and wearablecomputing, other types of personal ambulatory monitors, of varyingdegrees of sophistication, have become increasingly available. Forexample, adherents to the so-called “Quantified Self” movement combinewearable sensors and wearable computing to self-track activities oftheir daily lives, including inputs, states, and performance. The Nike+FuelBand, manufactured by Nike Inc., Beaverton, Oreg., for instance,provides an activity tracker that is worn on the wrist and allows thewearer to temporally track the number of foot steps taken each day andan estimation of the calories burned. The activity tracker can interfacewith a smart phone device to allow a wearer to monitor their progresstowards a fitness goal. Such quantified physiology, however, istypically tracked for only the personal use of the wearer and is nottime-correlated to physician-supervised monitoring.

Therefore, a need remains for an extended wear continuously recordingECG monitor practicably capable of being worn for a long period of timein both men and women and capable of recording atrial signals reliably.

A further need remains for facilities to integrate wider-rangingphysiological and “life tracking”-type data into long-term ECG andphysiological data monitoring.

SUMMARY

Physiological monitoring can be provided through a wearable monitor thatincludes two components, a flexible extended wear electrode patch and aremovable reusable monitor recorder. The wearable monitor sits centrally(in the midline) on the patient's chest along the sternum orientedtop-to-bottom. The placement of the wearable monitor in a location atthe sternal midline (or immediately to either side of the sternum), withits unique narrow “hourglass”-like shape, benefits long-term extendedwear by removing the requirement that ECG electrodes be continuallyplaced in the same spots on the skin throughout the monitoring period.Instead, the patient is free to place an electrode patch anywhere withinthe general region of the sternum, the area most likely to record highquality atrial signals or P-waves. The wearable monitor can alsointeroperate wirelessly with other wearable physiology and activitysensors and with wearable or mobile communications devices, includingso-called “smart phones,” to download monitoring data either inreal-time or in batches. The monitor recorder can also be equipped witha wireless transceiver to either provide data or other information to,or receive data or other information from, an interfacing wearablephysiology and activity sensor, or wearable or mobile communicationsdevices for relay to a further device, such as a server, analysis, orother purpose.

One embodiment provides a remotely-interfaceable electrocardiographypatch. The remotely-interfaceable electrocardiography patch includes abacking formed of a strip of material and an electrocardiographicelectrode on each end of the backing to capture electrocardiographicsignals. A flexible circuit includes a pair of circuit traceselectrically coupled to the electrocardiographic electrodes. A wirelesstransceiver communicates at least one of the electrocardiographicsignals and other physiological measures with one or more of aphysiology and activity sensor, communication device, server, andpersonal computer.

A further embodiment provides an electrocardiography patch. A backingforms an elongated strip with a mid-section connecting two ends of thebacking. The mid-section is narrower than the two ends of the backing.An electrocardiographic electrode is provided on each end of the backingto capture electrocardiographic signals. A flexible circuit includes apair of circuit traces electrically coupled to the electrocardiographicelectrodes. A wireless transceiver communicates at least a portion ofthe electrocardiographic signals.

A still further embodiment provides an electrocardiography monitor. Abacking forms an elongated strip with a mid-section connecting two endsof the backing. The mid-section is narrower than the two ends of thebacking. An electrocardiographic electrode is provided on each end ofthe backing to capture electrocardiographic signals. A flexible circuitincludes a pair of circuit traces electrically coupled to theelectrocardiographic electrodes. A wireless transceiver communicates atleast a portion of the electrocardiographic signals. A battery ispositioned on one of the ends of the backing and a processor is poweredby the battery. A memory is electrically interfaced with the processorand operable to store samples of the electrocardiographic signals

The monitoring patch is especially suited to the female anatomy. Thenarrow longitudinal midsection can fit nicely within the intermammarycleft of the breasts without inducing discomfort, whereas conventionalpatch electrodes are wide and, if adhesed between the breasts, wouldcause chafing, irritation, frustration, and annoyance, leading to lowpatient compliance.

The foregoing aspects enhance ECG monitoring performance and quality,facilitating long-term ECG recording, critical to accurate arrhythmiadiagnosis.

In addition, the foregoing aspects enhance comfort in women (and certainmen), but not irritation of the breasts, by placing the monitoring patchin the best location possible for optimizing the recording of cardiacsignals from the atrium, another feature critical to proper arrhythmiadiagnosis.

Finally, the foregoing aspects as relevant to monitoring are equallyapplicable to recording other physiological measures, such astemperature, respiratory rate, blood sugar, oxygen saturation, and bloodpressure, as well as other measures of body chemistry and physiology.

Still other embodiments will become readily apparent to those skilled inthe art from the following detailed description, wherein are describedembodiments by way of illustrating the best mode contemplated. As willbe realized, other and different embodiments are possible and theembodiments' several details are capable of modifications in variousobvious respects, all without departing from their spirit and the scope.Accordingly, the drawings and detailed description are to be regarded asillustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 and 2 are diagrams showing, by way of examples, an extended wearelectrocardiography and physiological sensor monitor respectively fittedto the sternal region of a female patient and a male patient.

FIG. 3 is a functional block diagram showing a system for remoteinterfacing of an extended wear electrocardiography and physiologicalsensor monitor in accordance with one embodiment.

FIG. 4 is a perspective view showing an extended wear electrode patchwith a monitor recorder inserted.

FIG. 5 is a perspective view showing the monitor recorder of FIG. 4.

FIG. 6 is a perspective view showing the extended wear electrode patchof FIG. 4 without a monitor recorder inserted.

FIG. 7 is a bottom plan view of the monitor recorder of FIG. 4.

FIG. 8 is a top view showing the flexible circuit of the extended wearelectrode patch of FIG. 4 when mounted above the flexible backing.

FIG. 9 is a functional block diagram showing the component architectureof the circuitry of the monitor recorder of FIG. 4.

FIG. 10 is a functional block diagram showing the circuitry of theextended wear electrode patch of FIG. 4.

FIG. 11 is a flow diagram showing a monitor recorder-implemented methodfor monitoring ECG data for use in the monitor recorder of FIG. 4.

FIG. 12 is a graph showing, by way of example, a typical ECG waveform.

FIG. 13 is a flow diagram showing a method for offloading and convertingECG and other physiological data from an extended wearelectrocardiography and physiological sensor monitor in accordance withone embodiment.

DETAILED DESCRIPTION

Physiological monitoring can be provided through a wearable monitor thatincludes two components, a flexible extended wear electrode patch and aremovable reusable monitor recorder. FIGS. 1 and 2 are diagrams showing,by way of examples, an extended wear electrocardiography andphysiological sensor monitor 12, including a monitor recorder 14 inaccordance with one embodiment, respectively fitted to the sternalregion of a female patient 10 and a male patient 11. The wearablemonitor 12 sits centrally (in the midline) on the patient's chest alongthe sternum 13 oriented top-to-bottom with the monitor recorder 14preferably situated towards the patient's head. In a further embodiment,the orientation of the wearable monitor 12 can be correctedpost-monitoring, as further described infra. The electrode patch 15 isshaped to fit comfortably and conformal to the contours of the patient'schest approximately centered on the sternal midline 16 (or immediatelyto either side of the sternum 13). The distal end of the electrode patch15 extends towards the Xiphoid process and, depending upon the patient'sbuild, may straddle the region over the Xiphoid process. The proximalend of the electrode patch 15, located under the monitor recorder 14, isbelow the manubrium and, depending upon patient's build, may straddlethe region over the manubrium.

The placement of the wearable monitor 12 in a location at the sternalmidline 16 (or immediately to either side of the sternum 13)significantly improves the ability of the wearable monitor 12 tocutaneously sense cardiac electric signals, particularly the P-wave (oratrial activity) and, to a lesser extent, the QRS interval signals inthe ECG waveforms that indicate ventricular activity, whilesimultaneously facilitating comfortable long-term wear for many weeks.The sternum 13 overlies the right atrium of the heart and the placementof the wearable monitor 12 in the region of the sternal midline 13 putsthe ECG electrodes of the electrode patch 15 in a location betteradapted to sensing and recording P-wave signals than other placementlocations, say, the upper left pectoral region or lateral thoracicregion or the limb leads. In addition, placing the lower or inferiorpole (ECG electrode) of the electrode patch 15 over (or near) theXiphoid process facilitates sensing of ventricular activity and providessuperior recordation of the QRS interval.

When operated standalone, the monitor recorder 14 of the extended wearelectrocardiography and physiological sensor monitor 12 senses andrecords the patient's ECG data into an onboard memory. In addition, thewearable monitor 12 can interoperate with other devices. FIG. 3 is afunctional block diagram showing a system 120 for remote interfacing ofan extended wear electrocardiography and physiological sensor monitor 12in accordance with one embodiment. The monitor recorder 14 is a reusablecomponent that can be fitted during patient monitoring into anon-conductive receptacle provided on the electrode patch 15, as furtherdescribed infra with reference to FIG. 4, and later removed foroffloading of stored ECG data or to receive revised programming. Themonitor recorder 14 can then be connected to a download station 125,which could be a programmer or other device that permits the retrievalof stored ECG monitoring data, execution of diagnostics on orprogramming of the monitor recorder 14, or performance of otherfunctions. The monitor recorder 14 has a set of electrical contacts (notshown) that enable the monitor recorder 14 to physically interface to aset of terminals 128 on a paired receptacle 127 of the download station125. In turn, the download station 125 executes a communications oroffload program 126 (“Offload”) or similar program that interacts withthe monitor recorder 14 via the physical interface to retrieve thestored ECG monitoring data. The download station 125 could be a server,personal computer, tablet or handheld computer, smart mobile device, orpurpose-built programmer designed specific to the task of interfacingwith a monitor recorder 14. Still other forms of download station 125are possible.

Upon retrieving stored ECG monitoring data from a monitor recorder 14,middleware first operates on the retrieved data to adjust the ECGcapture quality, as necessary, and to convert the retrieved data into aformat suitable for use by third party post-monitoring analysissoftware, as further described infra with reference to FIG. 13. Theformatted data can then be retrieved from the download station 125 overa hard link 135 using a control program 137 (“Ctl”) or analogousapplication executing on a personal computer 136 or other connectablecomputing device, via a communications link (not shown), whether wiredor wireless, or by physical transfer of storage media (not shown). Thepersonal computer 136 or other connectable device may also executemiddleware that converts ECG data and other information into a formatsuitable for use by a third-party post-monitoring analysis program, asfurther described infra with reference to FIG. 13. Note that formatteddata stored on the personal computer 136 would have to be maintained andsafeguarded in the same manner as electronic medical records (EMRs) 134in the secure database 124, as further discussed infra. In a furtherembodiment, the download station 125 is able to directly interface withother devices over a computer communications network 121, which could besome combination of a local area network and a wide area network,including the Internet, over a wired or wireless connection.

A client-server model could be used to employ a server 122 to remotelyinterface with the download station 125 over the network 121 andretrieve the formatted data or other information. The server 122executes a patient management program 123 (“Mgt”) or similar applicationthat stores the retrieved formatted data and other information in asecure database 124 cataloged in that patient's EMRs 134. In addition,the patient management program 123 could manage a subscription servicethat authorizes a monitor recorder 14 to operate for a set period oftime or under pre-defined operational parameters.

The patient management program 123, or other trusted application, alsomaintains and safeguards the secure database 124 to limit access topatient EMRs 134 to only authorized parties for appropriate medical orother uses, such as mandated by state or federal law, such as under theHealth Insurance Portability and Accountability Act (HIPAA) or per theEuropean Union's Data Protection Directive. For example, a physician mayseek to review and evaluate his patient's ECG monitoring data, assecurely stored in the secure database 124. The physician would executean application program 130 (“Pgm”), such as a post-monitoring ECGanalysis program, on a personal computer 129 or other connectablecomputing device, and, through the application 130, coordinate access tohis patient's EMRs 134 with the patient management program 123. Otherschemes and safeguards to protect and maintain the integrity of patientEMRs 134 are possible.

The wearable monitor 12 can interoperate wirelessly with other wearablephysiology and activity sensors 131 and with wearable or mobilecommunications devices 133. Wearable physiology and activity sensors 131encompass a wide range of wirelessly interconnectable devices thatmeasure or monitor data physical to the patient's body, such as heartrate, temperature, blood pressure, and so forth; physical states, suchas movement, sleep, footsteps, and the like; and performance, includingcalories burned or estimated blood glucose level. These devicesoriginate both within the medical community to sense and recordtraditional medical physiology that could be useful to a physician inarriving at a patient diagnosis or clinical trajectory, as well as fromoutside the medical community, from, for instance, sports or lifestyleproduct companies who seek to educate and assist individuals withself-quantifying interests.

Frequently, wearable physiology and activity sensors 131 are capable ofwireless interfacing with wearable or mobile communications devices 133,particularly smart mobile devices, including so-called “smart phones,”to download monitoring data either in real-time or in batches. Thewearable or mobile communications device 133 executes an application(“App”) that can retrieve the data collected by the wearable physiologyand activity sensor 131 and evaluate the data to generate information ofinterest to the wearer, such as an estimation of the effectiveness ofthe wearer's exercise efforts. Still other wearable or mobilecommunications device 133 functions on the collected data are possible.

The wearable or mobile communications devices 133 could also serve as aconduit for providing the data collected by the wearable physiology andactivity sensor 131 to a server 122, or, similarly, the wearablephysiology and activity sensor 131 could itself directly provide thecollected data to the server 122. The server 122 could then merge thecollected data into the wearer's EMRs 134 in the secure database 124, ifappropriate (and permissible), or the server 122 could perform ananalysis of the collected data, perhaps based by comparison to apopulation of like wearers of the wearable physiology and activitysensor 131. Still other server 122 functions on the collected data arepossible.

Finally, the monitor recorder 14 can also be equipped with a wirelesstransceiver, as further described infra with reference to FIGS. 9 and10. Thus, when wireless-enabled, both wearable physiology and activitysensors 131 and wearable or mobile communications devices 133 couldwirelessly interface with the monitor recorder 14, which could eitherprovide data or other information to, or receive data or otherinformation from an interfacing device for relay to a further device,such as the server 122, analysis, or other purpose. In addition, themonitor recorder 14 could wirelessly interface directly with the server122, personal computer 129, or other computing device connectable overthe network 121, when the monitor recorder 14 is appropriately equippedfor interfacing with such devices. Still other types of remoteinterfacing of the monitor recorder 14 are possible.

During use, the electrode patch 15 is first adhesed to the skin alongthe sternal midline 16 (or immediately to either side of the sternum13). A monitor recorder 14 is then snapped into place on the electrodepatch 15 to initiate ECG monitoring. FIG. 4 is a perspective viewshowing an extended wear electrode patch 15 with a monitor recorder 14in accordance with one embodiment inserted. The body of the electrodepatch 15 is preferably constructed using a flexible backing 20 formed asan elongated strip 21 of wrap knit or similar stretchable material witha narrow longitudinal mid-section 23 evenly tapering inward from bothsides. A pair of cut-outs 22 between the distal and proximal ends of theelectrode patch 15 create a narrow longitudinal midsection 23 or“isthmus” and defines an elongated “hourglass”-like shape, when viewedfrom above.

The electrode patch 15 incorporates features that significantly improvewearability, performance, and patient comfort throughout an extendedmonitoring period. During wear, the electrode patch 15 is susceptible topushing, pulling, and torqueing movements, including compressional andtorsional forces when the patient bends forward, and tensile andtorsional forces when the patient leans backwards. To counter thesestress forces, the electrode patch 15 incorporates strain and crimpreliefs, such as described in commonly-assigned U.S. Patent, entitled“Extended Wear Electrocardiography Patch,” U.S. Pat. No. 9,545,204,issued Jan. 17, 2017, the disclosure of which is incorporated byreference. In addition, the cut-outs 22 and longitudinal midsection 23help minimize interference with and discomfort to breast tissue,particularly in women (and gynecomastic men). The cut-outs 22 andlongitudinal midsection 23 further allow better conformity of theelectrode patch 15 to sternal bowing and to the narrow isthmus of flatskin that can occur along the bottom of the intermammary cleft betweenthe breasts, especially in buxom women. The cut-outs 22 and longitudinalmidsection 23 help the electrode patch 15 fit nicely between a pair offemale breasts in the intermammary cleft. Still other shapes, cut-outsand conformities to the electrode patch 15 are possible.

The monitor recorder 14 removably and reusably snaps into anelectrically non-conductive receptacle 25 during use. The monitorrecorder 14 contains electronic circuitry for recording and storing thepatient's electrocardiography as sensed via a pair of ECG electrodesprovided on the electrode patch 15, such as described incommonly-assigned U.S. Patent, entitled “Extended Wear AmbulatoryElectrocardiography and Physiological Sensor Monitor,” U.S. Pat. No.9,730,593, issued Aug. 15, 2017, the disclosure which is incorporated byreference. The non-conductive receptacle 25 is provided on the topsurface of the flexible backing 20 with a retention catch 26 and tensionclip 27 molded into the non-conductive receptacle 25 to conformablyreceive and securely hold the monitor recorder 14 in place.

The monitor recorder 14 includes a sealed housing that snaps into placein the non-conductive receptacle 25. FIG. 5 is a perspective viewshowing the monitor recorder 14 of FIG. 4. The sealed housing 50 of themonitor recorder 14 intentionally has a rounded isoscelestrapezoidal-like shape 52, when viewed from above, such as described incommonly-assigned U.S. Design Patent, entitled “ElectrocardiographyMonitor,” No. D717,955, issued Nov. 18, 2014, the disclosure of which isincorporated by reference. The edges 51 along the top and bottomsurfaces are rounded for patient comfort. The sealed housing 50 isapproximately 47 mm long, 23 mm wide at the widest point, and 7 mm high,excluding a patient-operable tactile-feedback button 55. The sealedhousing 50 can be molded out of polycarbonate, ABS, or an alloy of thosetwo materials. The button 55 is waterproof and the button's top outersurface is molded silicon rubber or similar soft pliable material. Aretention detent 53 and tension detent 54 are molded along the edges ofthe top surface of the housing 50 to respectively engage the retentioncatch 26 and the tension clip 27 molded into non-conductive receptacle25. Other shapes, features, and conformities of the sealed housing 50are possible.

The electrode patch 15 is intended to be disposable. The monitorrecorder 14, however, is reusable and can be transferred to successiveelectrode patches 15 to ensure continuity of monitoring. The placementof the wearable monitor 12 in a location at the sternal midline 16 (orimmediately to either side of the sternum 13) benefits long-termextended wear by removing the requirement that ECG electrodes becontinually placed in the same spots on the skin throughout themonitoring period. Instead, the patient is free to place an electrodepatch 15 anywhere within the general region of the sternum 13.

As a result, at any point during ECG monitoring, the patient's skin isable to recover from the wearing of an electrode patch 15, whichincreases patient comfort and satisfaction, while the monitor recorder14 ensures ECG monitoring continuity with minimal effort. A monitorrecorder 14 is merely unsnapped from a worn out electrode patch 15, theworn out electrode patch 15 is removed from the skin, a new electrodepatch 15 is adhered to the skin, possibly in a new spot immediatelyadjacent to the earlier location, and the same monitor recorder 14 issnapped into the new electrode patch 15 to reinitiate and continue theECG monitoring.

During use, the electrode patch 15 is first adhered to the skin in thesternal region. FIG. 6 is a perspective view showing the extended wearelectrode patch 15 of FIG. 4 without a monitor recorder 14 inserted. Aflexible circuit 32 is adhered to each end of the flexible backing 20. Adistal circuit trace 33 and a proximal circuit trace (not shown)electrically couple ECG electrodes (not shown) to a pair of electricalpads 34. The electrical pads 34 are provided within a moisture-resistantseal 35 formed on the bottom surface of the non-conductive receptacle25. When the monitor recorder 14 is securely received into thenon-conductive receptacle 25, that is, snapped into place, theelectrical pads 34 interface to electrical contacts (not shown)protruding from the bottom surface of the monitor recorder 14, and themoisture-resistant seal 35 enables the monitor recorder 14 to be worn atall times, even during bathing or other activities that could expose themonitor recorder 14 to moisture.

In addition, a battery compartment 36 is formed on the bottom surface ofthe non-conductive receptacle 25, and a pair of battery leads (notshown) electrically interface the battery to another pair of theelectrical pads 34. The battery contained within the battery compartment35 can be replaceable, rechargeable or disposable.

The monitor recorder 14 draws power externally from the battery providedin the non-conductive receptacle 25, thereby uniquely obviating the needfor the monitor recorder 14 to carry a dedicated power source. FIG. 7 isa bottom plan view of the monitor recorder 14 of FIG. 4. A cavity 58 isformed on the bottom surface of the sealed housing 50 to accommodate theupward projection of the battery compartment 36 from the bottom surfaceof the non-conductive receptacle 25, when the monitor recorder 14 issecured in place on the non-conductive receptacle 25. A set ofelectrical contacts 56 protrude from the bottom surface of the sealedhousing 50 and are arranged in alignment with the electrical pads 34provided on the bottom surface of the non-conductive receptacle 25 toestablish electrical connections between the electrode patch 15 and themonitor recorder 14. In addition, a seal coupling 57 circumferentiallysurrounds the set of electrical contacts 56 and securely mates with themoisture-resistant seal 35 formed on the bottom surface of thenon-conductive receptacle 25.

The placement of the flexible backing 20 on the sternal midline 16 (orimmediately to either side of the sternum 13) also helps to minimize theside-to-side movement of the wearable monitor 12 in the left- andright-handed directions during wear. To counter the dislodgment of theflexible backing 20 due to compressional and torsional forces, a layerof non-irritating adhesive, such as hydrocolloid, is provided at leastpartially on the underside, or contact, surface of the flexible backing20, but only on the distal end 30 and the proximal end 31. As a result,the underside, or contact surface of the longitudinal midsection 23 doesnot have an adhesive layer and remains free to move relative to theskin. Thus, the longitudinal midsection 23 forms a crimp relief thatrespectively facilitates compression and twisting of the flexiblebacking 20 in response to compressional and torsional forces. Otherforms of flexible backing crimp reliefs are possible.

Unlike the flexible backing 20, the flexible circuit 32 is only able tobend and cannot stretch in a planar direction. The flexible circuit 32can be provided either above or below the flexible backing 20. FIG. 8 isa top view showing the flexible circuit 32 of the extended wearelectrode patch 15 of FIG. 4 when mounted above the flexible backing 20.A distal ECG electrode 38 and proximal ECG electrode 39 are respectivelycoupled to the distal and proximal ends of the flexible circuit 32. Astrain relief 40 is defined in the flexible circuit 32 at a locationthat is partially underneath the battery compartment 36 when theflexible circuit 32 is affixed to the flexible backing 20. The strainrelief 40 is laterally extendable to counter dislodgment of the ECGelectrodes 38, 39 due to tensile and torsional forces. A pair of strainrelief cutouts 41 partially extend transversely from each opposite sideof the flexible circuit 32 and continue longitudinally towards eachother to define in ‘S’-shaped pattern, when viewed from above. Thestrain relief respectively facilitates longitudinal extension andtwisting of the flexible circuit 32 in response to tensile and torsionalforces. Other forms of circuit board strain relief are possible.

ECG monitoring and other functions performed by the monitor recorder 14are provided through a micro controlled architecture. FIG. 9 is afunctional block diagram showing the component architecture of thecircuitry 60 of the monitor recorder 14 of FIG. 4. The circuitry 60 isexternally powered through a battery provided in the non-conductivereceptacle 25 (shown in FIG. 6). Both power and raw ECG signals, whichoriginate in the pair of ECG electrodes 38, 39 (shown in FIG. 8) on thedistal and proximal ends of the electrode patch 15, are received throughan external connector 65 that mates with a corresponding physicalconnector on the electrode patch 15. The external connector 65 includesthe set of electrical contacts 56 that protrude from the bottom surfaceof the sealed housing 50 and which physically and electrically interfacewith the set of pads 34 provided on the bottom surface of thenon-conductive receptacle 25. The external connector includes electricalcontacts 56 for data download, microcontroller communications, power,analog inputs, and a peripheral expansion port. The arrangement of thepins on the electrical connector 65 of the monitor recorder 14 and thedevice into which the monitor recorder 14 is attached, whether anelectrode patch 15 or download station (not shown), follow the sameelectrical pin assignment convention to facilitate interoperability. Theexternal connector 65 also serves as a physical interface to a downloadstation that permits the retrieval of stored ECG monitoring data,communication with the monitor recorder 14, and performance of otherfunctions.

Operation of the circuitry 60 of the monitor recorder 14 is managed by amicrocontroller 61. The micro-controller 61 includes a program memoryunit containing internal flash memory that is readable and writeable.The internal flash memory can also be programmed externally. Themicro-controller 61 draws power externally from the battery provided onthe electrode patch 15 via a pair of the electrical contacts 56. Themicrocontroller 61 connects to the ECG front end circuit 63 thatmeasures raw cutaneous electrical signals and generates an analog ECGsignal representative of the electrical activity of the patient's heartover time.

The circuitry 60 of the monitor recorder 14 also includes a flash memory62, which the micro-controller 61 uses for storing ECG monitoring dataand other physiology and information. The flash memory 62 also drawspower externally from the battery provided on the electrode patch 15 viaa pair of the electrical contacts 56. Data is stored in a serial flashmemory circuit, which supports read, erase and program operations over acommunications bus. The flash memory 62 enables the microcontroller 61to store digitized ECG data. The communications bus further enables theflash memory 62 to be directly accessed externally over the externalconnector 65 when the monitor recorder 14 is interfaced to a downloadstation.

The circuitry 60 of the monitor recorder 14 further includes anactigraphy sensor 64 implemented as a 3-axis accelerometer. Theaccelerometer may be configured to generate interrupt signals to themicrocontroller 61 by independent initial wake up and free fall events,as well as by device position. In addition, the actigraphy provided bythe accelerometer can be used during post-monitoring analysis to correctthe orientation of the monitor recorder 14 if, for instance, the monitorrecorder 14 has been inadvertently installed upside down, that is, withthe monitor recorder 14 oriented on the electrode patch 15 towards thepatient's feet, as well as for other event occurrence analyses, such asdescribed in commonly-assigned U.S. Pat. No. 9,737,224, issued Aug. 22,2017, the disclosure of which is incorporated by reference.

The circuitry 60 of the monitor recorder 14 includes a wirelesstransceiver 69 that can provides wireless interfacing capabilities. Thewireless transceiver 69 also draws power externally from the batteryprovided on the electrode patch 15 via a pair of the electrical contacts56. The wireless transceiver 69 can be implemented using one or moreforms of wireless communications, including the IEEE 802.11 computercommunications standard, that is Wi-Fi; the 4G mobile phone mobilecommunications standard; the Bluetooth data exchange standard; or otherwireless communications or data exchange standards and protocols. Thetype of wireless interfacing capability could limit the range ofinteroperability of the monitor recorder 14; for instance,Bluetooth-based implementations are designed for low power consumptionwith a short communications range.

The microcontroller 61 includes an expansion port that also utilizes thecommunications bus. External devices, separately drawing powerexternally from the battery provided on the electrode patch 15 or othersource, can interface to the microcontroller 61 over the expansion portin half duplex mode. For instance, an external physiology sensor can beprovided as part of the circuitry 60 of the monitor recorder 14, or canbe provided on the electrode patch 15 with communication with themicro-controller 61 provided over one of the electrical contacts 56. Thephysiology sensor can include an SpO₂ sensor, blood pressure sensor,temperature sensor, respiratory rate sensor, glucose sensor, airflowsensor, volumetric pressure sensing, or other types of sensor ortelemetric input sources. For instance, the integration of an airflowsensor is described in commonly-assigned U.S. Pat. No. 9,364,155, issuedJun. 14, 2016, the disclosure which is incorporated by reference.

Finally, the circuitry 60 of the monitor recorder 14 includespatient-interfaceable components, including a tactile feedback button66, which a patient can press to mark events or to perform otherfunctions, and a buzzer 67, such as a speaker, magnetic resonator orpiezoelectric buzzer. The buzzer 67 can be used by the microcontroller61 to output feedback to a patient such as to confirm power up andinitiation of ECG monitoring. Still other components as part of thecircuitry 60 of the monitor recorder 14 are possible.

While the monitor recorder 14 operates under micro control, most of theelectrical components of the electrode patch 15 operate passively. FIG.10 is a functional block diagram showing the circuitry 70 of theextended wear electrode patch 15 of FIG. 4. The circuitry 70 of theelectrode patch 15 is electrically coupled with the circuitry 60 of themonitor recorder 14 through an external connector 74. The externalconnector 74 is terminated through the set of pads 34 provided on thebottom of the non-conductive receptacle 25, which electrically mate tocorresponding electrical contacts 56 protruding from the bottom surfaceof the sealed housing 50 to electrically interface the monitor recorder14 to the electrode patch 15.

The circuitry 70 of the electrode patch 15 performs three primaryfunctions. First, a battery 71 is provided in a battery compartmentformed on the bottom surface of the non-conductive receptacle 25. Thebattery 71 is electrically interfaced to the circuitry 60 of the monitorrecorder 14 as a source of external power. The unique provisioning ofthe battery 71 on the electrode patch 15 provides several advantages.First, the locating of the battery 71 physically on the electrode patch15 lowers the center of gravity of the overall wearable monitor 12 andthereby helps to minimize shear forces and the effects of movements ofthe patient and clothing. Moreover, the housing 50 of the monitorrecorder 14 is sealed against moisture and providing power externallyavoids having to either periodically open the housing 50 for the batteryreplacement, which also creates the potential for moisture intrusion andhuman error, or to recharge the battery, which can potentially take themonitor recorder 14 off line for hours at a time. In addition, theelectrode patch 15 is intended to be disposable, while the monitorrecorder 14 is a reusable component. Each time that the electrode patch15 is replaced, a fresh battery is provided for the use of the monitorrecorder 14, which enhances ECG monitoring performance quality andduration of use. Finally, the architecture of the monitor recorder 14 isopen, in that other physiology sensors or components can be added byvirtue of the expansion port of the microcontroller 61. Requiring thoseadditional sensors or components to draw power from a source external tothe monitor recorder 14 keeps power considerations independent of themonitor recorder 14. Thus, a battery of higher capacity could beintroduced when needed to support the additional sensors or componentswithout effecting the monitor recorders circuitry 60.

Second, the pair of ECG electrodes 38, 39 respectively provided on thedistal and proximal ends of the flexible circuit 32 are electricallycoupled to the set of pads 34 provided on the bottom of thenon-conductive receptacle 25 by way of their respective circuit traces33, 37. The signal ECG electrode 39 includes a protection circuit 72,which is an inline resistor that protects the patient from excessiveleakage current.

Last, in a further embodiment, the circuitry 70 of the electrode patch15 includes a cryptographic circuit 73 to authenticate an electrodepatch 15 for use with a monitor recorder 14. The cryptographic circuit73 includes a device capable of secure authentication and validation.The cryptographic device 73 ensures that only genuine, non-expired,safe, and authenticated electrode patches 15 are permitted to providemonitoring data to a monitor recorder 14, such as described incommonly-assigned U.S. Pat. No. 9,655,538, issued May 23, 2017, thedisclosure which is incorporated by reference.

In a further embodiment, the circuitry 70 of the electrode patch 15includes a wireless transceiver 75, in lieu the including of thewireless transceiver 69 in the circuitry 60 of the monitor recorder 14,which interfaces with the microcontroller 61 over the microcontroller'sexpansion port via the external connector 74.

The monitor recorder 14 continuously monitors the patient's heart rateand physiology. FIG. 11 is a flow diagram showing a monitorrecorder-implemented method 100 for monitoring ECG data for use in themonitor recorder 14 of FIG. 4. Initially, upon being connected to theset of pads 34 provided with the non-conductive receptacle 25 when themonitor recorder 14 is snapped into place, the microcontroller 61executes a power up sequence (step 101). During the power up sequence,the voltage of the battery 71 is checked, the state of the flash memory62 is confirmed, both in terms of operability check and availablecapacity, and microcontroller operation is diagnostically confirmed. Ina further embodiment, an authentication procedure between themicrocontroller 61 and the electrode patch 15 are also performed.

Following satisfactory completion of the power up sequence, an iterativeprocessing loop (steps 102-109) is continually executed by themicrocontroller 61. During each iteration (step 102) of the processingloop, the ECG frontend 63 (shown in FIG. 9) continually senses thecutaneous ECG electrical signals (step 103) via the ECG electrodes 38,29 and is optimized to maintain the integrity of the P-wave. A sample ofthe ECG signal is read (step 104) by the microcontroller 61 by samplingthe analog ECG signal output front end 63. FIG. 12 is a graph showing,by way of example, a typical ECG waveform 110. The x-axis representstime in approximate units of tenths of a second. The y-axis representscutaneous electrical signal strength in approximate units of millivolts.The P-wave 111 has a smooth, normally upward, that is, positive,waveform that indicates atrial depolarization. The QRS complex usuallybegins with the downward deflection of a Q wave 112, followed by alarger upward deflection of an R-wave 113, and terminated with adownward waveform of the S wave 114, collectively representative ofventricular depolarization. The T wave 115 is normally a modest upwardwaveform, representative of ventricular depolarization, while the U wave116, often not directly observable, indicates the recovery period of thePurkinje conduction fibers.

Sampling of the R-to-R interval enables heart rate informationderivation. For instance, the R-to-R interval represents the ventricularrate and rhythm, while the P-to-P interval represents the atrial rateand rhythm. Importantly, the PR interval is indicative ofatrioventricular (AV) conduction time and abnormalities in the PRinterval can reveal underlying heart disorders, thus representinganother reason why the P-wave quality achievable by the extended wearambulatory electrocardiography and physiological sensor monitordescribed herein is medically unique and important. The long-termobservation of these ECG indicia, as provided through extended wear ofthe wearable monitor 12, provides valuable insights to the patient'scardiac function and overall well-being.

Each sampled ECG signal, in quantized and digitized form, is temporarilystaged in buffer (step 105), pending compression preparatory to storagein the flash memory 62 (step 106). Following compression, the compressedECG digitized sample is again buffered (step 107), then written to theflash memory 62 (step 108) using the communications bus. Processingcontinues (step 109), so long as the monitoring recorder 14 remainsconnected to the electrode patch 15 (and storage space remains availablein the flash memory 62), after which the processing loop is exited andexecution terminates. Still other operations and steps are possible.

In a further embodiment, the monitor recorder 14 also continuouslyreceives data from wearable physiology and activity sensors 131 andwearable or mobile communications devices 133 (shown in FIG. 3). Thedata is received in a conceptually-separate execution thread as part ofthe iterative processing loop (steps 102-109) continually executed bythe microcontroller 61. During each iteration (step 102) of theprocessing loop, if wireless data is available (step 140), a sample ofthe wireless is read (step 141) by the microcontroller 61 and, ifnecessary, converted into a digital signal by the onboard ADC of themicrocontroller 61. Each wireless data sample, in quantized anddigitized form, is temporarily staged in buffer (step 142), pendingcompression preparatory to storage in the flash memory 62 (step 143).Following compression, the compressed wireless data sample is againbuffered (step 144), then written to the flash memory 62 (step 145)using the communications bus. Processing continues (step 109), so longas the monitoring recorder 14 remains connected to the electrode patch15 (and storage space remains available in the flash memory 62), afterwhich the processing loop is exited and execution terminates. Stillother operations and steps are possible.

The monitor recorder 14 stores ECG data and other information in theflash memory 62 (shown in FIG. 9) using a proprietary format thatincludes data compression. As a result, data retrieved from a monitorrecorder 14 must first be converted into a format suitable for use bythird party post-monitoring analysis software. FIG. 13 is a flow diagramshowing a method 150 for offloading and converting ECG and otherphysiological data from an extended wear electrocardiography andphysiological sensor monitor 12 in accordance with one embodiment. Themethod 150 can be implemented in software and execution of the softwarecan be performed on a download station 125, which could be a programmeror other device, or a computer system, including a server 122 orpersonal computer 129, such as further described supra with reference toFIG. 3, as a series of process or method modules or steps. Forconvenience, the method 150 will be described in the context of beingperformed by a personal computer 136 or other connectable computingdevice (shown in FIG. 3) as middleware that converts ECG data and otherinformation into a format suitable for use by a third-partypost-monitoring analysis program. Execution of the method 150 by acomputer system would be analogous mutatis mutandis.

Initially, the download station 125 is connected to the monitor recorder14 (step 151), such as by physically interfacing to a set of terminals128 on a paired receptacle 127 or by wireless connection, if available.The data stored on the monitor recorder 14, including ECG andphysiological monitoring data, other recorded data, and otherinformation are retrieved (step 152) over a hard link 135 using acontrol program 137 (“Ctl”) or analogous application executing on apersonal computer 136 or other connectable computing device.

The data retrieved from the monitor recorder 14 is in a proprietarystorage format and each datum of recorded ECG monitoring data, as wellas any other physiological data or other information, must be converted,so that the data can be used by a third-party post-monitoring analysisprogram. Each datum of ECG monitoring data is converted by themiddleware (steps 153-159) in an iterative processing loop. During eachiteration (step 153), the ECG datum is read (step 154) and, ifnecessary, the gain of the ECG signal is adjusted (step 155) tocompensate, for instance, for relocation or replacement of the electrodepatch 15 during the monitoring period.

In addition, depending upon the configuration of the wearable monitor12, other physiological data (or other information), including patientevents, such as a fall, peak activity level, sleep detection, Detectionof patient activity levels and states, and so on, may be recorded alongwith the ECG monitoring data. For instance, actigraphy data may havebeen sampled by the actigraphy sensor 64 based on a sensed eventoccurrence, such as a sudden change in orientation due to the patienttaking a fall. In response, the monitor recorder 14 will embed theactigraphy data samples into the stream of data, including ECGmonitoring data, that is recorded to the flash memory 62 by themicro-controller 61. Post-monitoring, the actigraphy data is temporallymatched to the ECG data to provide the proper physiological context tothe sensed event occurrence. As a result, the three-axis actigraphysignal is turned into an actionable event occurrence that is provided,through conversion by the middleware, to third party post-monitoringanalysis programs, along with the ECG recordings contemporaneous to theevent occurrence. Other types of processing of the other physiologicaldata (or other information) are possible.

Thus, during execution of the middleware, any other physiological data(or other information) that has been embedded into the recorded ECGmonitoring data is read (step 156) and time-correlated to the time frameof the ECG signals that occurred at the time that the otherphysiological data (or other information) was noted (step 157). Finally,the ECG datum, signal gain adjusted, if appropriate, and otherphysiological data, if applicable and as time-correlated, are stored ina format suitable to the backend software (step 158) used inpost-monitoring analysis.

In a further embodiment, the other physiological data, if apropos, isembedded within an unused ECG track. For example, the SCP-ENG standardallows multiple ECG channels to be recorded into a single ECG record.The monitor recorder 14, though, only senses one ECG channel. The otherphysiological data can be stored into an additional ECG channel, whichwould otherwise be zero-padded or altogether omitted. The backendsoftware would then be able to read the other physiological data incontext with the single channel of ECG monitoring data recorded by themonitor recorder 14, provided the backend software implemented changesnecessary to interpret the other physiological data. Still other formsof embedding of the other physiological data with formatted ECGmonitoring data, or of providing the other physiological data in aseparate manner, are possible.

Processing continues (step 159) for each remaining ECG datum, afterwhich the processing loop is exited and execution terminates. Stillother operations and steps are possible.

While the invention has been particularly shown and described asreferenced to the embodiments thereof, those skilled in the art willunderstand that the foregoing and other changes in form and detail maybe made therein without departing from the spirit and scope.

What is claimed is:
 1. An electrocardiography patch, comprising: abacking comprising an elongated strip with a mid-section connecting twoends of the backing, wherein the mid-section is narrower than the twoends of the backing; an electrocardiographic electrode on each end ofthe backing to capture electrocardiographic signals; a flexible circuitcomprising a pair of circuit traces electrically coupled to theelectrocardiographic electrodes; and a wireless transceiver tocommunicate at least a portion of the electrocardiographic signals. 2.An electrocardiography patch according to claim 1, further comprising:an accelerometer provided on the backing.
 3. An electrocardiographypatch according to claim 1, further comprising: a physiology sensorprovided on the backing to measure body temperature.
 4. Anelectrocardiography patch according to claim 1, wherein each of the endsof the backing is rounded on an outer edge.
 5. An electrocardiographypatch according to claim 1, further comprising: a physiology andactivity sensor provided on the backing to measure one or more of heartrate, temperature, blood pressure, movement, sleep, footsteps, caloriesburned and estimated blood glucose level.
 6. An electrocardiographypatch according to claim 1, wherein the electrocardiographic signals areconverted to a different format and processed.
 7. An electrocardiographypatch according to claim 6, wherein the formatted electrocardiographicsignals are retrieved by one of a server, a client computer and a mobiledevice via the wireless transceiver.
 8. An electrocardiography patchaccording to claim 1, wherein the electrodes are exposed on a contactsurface of the backing.
 9. An electrocardiography patch according toclaim 1, further comprising: a hydrocolloid adhesive provided on atleast a portion of a contact surface of the backing.
 10. Anelectrocardiography patch according to claim 9, wherein the hydrocolloidadhesive is provided on the ends of the backing, on the contact surface.11. An electrocardiography monitor, comprising: a backing comprising anelongated strip with a mid-section connecting two ends of the backing,wherein the mid-section is narrower than the two ends of the backing; anelectrocardiographic electrode on each end of the backing to captureelectrocardiographic signals; a flexible circuit comprising a pair ofcircuit traces electrically coupled to the electrocardiographicelectrodes; a wireless transceiver to communicate at least a portion ofthe electrocardiographic signals; a battery on one of the ends of thebacking; a processor powered by the battery; and memory electricallyinterfaced with the processor and operable to store samples of theelectrocardiographic signals.
 12. An electrocardiography monitoraccording to claim 11, further comprising: an accelerometer provided onthe backing.
 13. An electrocardiography monitor according to claim 11,further comprising: a physiology sensor provided on the backing tomeasure body temperature.
 14. An electrocardiography monitor accordingto claim 11, wherein each of the ends of the backing is rounded on anouter edge.
 15. An electrocardiography monitor according to claim 11,further comprising: a physiology and activity sensor provided on thebacking to measure one or more of heart rate, temperature, bloodpressure, movement, sleep, footsteps, calories burned and estimatedblood glucose level.
 16. An electrocardiography monitor according toclaim 11, wherein the electrocardiographic signals are converted to adifferent format and processed.
 17. An electrocardiography monitoraccording to claim 16, wherein the formatted electrocardiographicsignals are retrieved by one of a server, a client computer and a mobiledevice via the wireless transceiver.
 18. An electrocardiography monitoraccording to claim 11, wherein the electrodes are exposed on a contactsurface of the backing.
 19. An electrocardiography monitor according toclaim 11, further comprising: a hydrocolloid adhesive provided on atleast a portion of a contact surface of the backing.
 20. Anelectrocardiography monitor according to claim 19, wherein thehydrocolloid adhesive is provided on the ends of the backing, on thecontact surface.